Gas-inflated airship



April 10, 1928.

E. LEMPERTZ GAS INFLATED AIRSHIP Filed July 19, 1926 2 r w A f 0 7 8 flit 1 C k 4 1 We hi3 M M ,5

Patented Apr. 10, 1928.

UNITED STATES PATENT OFFICE.-

sssmmnn LEMBERTZ, on FRIEDRICHSHAFEN, GERMANY, assrcmon T0 LUFTSCHIFF-BAU ZEPPELHI GESELLSCHAFT MIT BESCHR'A'NKTEB. HAFTUNG, 0s FRIEDBIOHS-KAREN, GERMANY.

GAS-INFLATED AIRSHIP.

Application filed July 19, 1926, Serial No. 123,316, and in GermanyFebruary 1 8, 1926.

My invention relates to airships and more especially to airships whichare supported by lifting gas and are propelled by means of an internalcombustion engine.

The weight of such ships comprising hull, engine, outfit, and also itsdisposable lift is carried by means of its lifting gas. This gas must beofvery low specific gravity so that the difference between its weightper unit of space from that of the surrounding air may be aslarge aspossible. It has become normal to use hydrogen as lifting gas inairships. Another. lifting gas is helium, which has the advantage overhydrogen of being non-inflammable but helium is of a much higher pricethan hydrogen because of its scarcit and its costly manufacturingprocess. hat is why helium-inflated airships must be operated in a verycareful manner so as to avoid any unnecessary loss of s.

'flie airship while travellin uses up the fuel which it has aboard for t1e purpose of drivin the engines. Generally such fuel is gaso ine insheet metal tanks. The weight of this fuel is compensated by an adequateportion of the ships gas space inflated by the lifting gas. Consumptionof the fuel in the motors while travelling reduces the weight to becarried by the ship, because the exhaust gases are allowed to escapeinto the atmosphere. Thus-the ship will be getting lighter and lighterwhile travelling through the air. A certain amount of the surplus liftmay be compensated by turning the ships nose downwards thereby creatinga dynamic moment holding the ship down' but only while it is beingpropelled. As soon as the engines are stopped or when the surplus liftexceeds the dynamic downward moment, the shi will rise and an adequateportion of the lifting gas will be expelled by the automatic gas valveswhich are necessary to prevent the gas bags from being torn because ofthe increase of inner gas pressure compared with the outside airpressure. Rising of the airship may be arrested by letting out anadequate portion of lifting gas through the valvesto be operated atwill. But--espeeially when travelling overlong ihstanees whenconsiderable v fuel weight Wlll be cons umedit will be indispensable tolet gas escape while travelling and before landing to get the shipapproximately to equilibrium.

The main object of my invention is to procure suchapproximate,equilibrium during the flight and before the landing of theair ship with a minimum of loss'in lifting gas.

A secondar object is a considerable saving 1n the li ting gas capacityfor an airship of a certain performance.

A further object is the saving of weight in the airship structure.

There will be connected with my invention other advantages which will bepointed out later or which will appeal to the expert without furtherexplanation.

I attain all these advantages by applying a special method of operationwhich c0nsists mainly in using a gaseous fuel for the engines instead ofa liquid one. But my fuel gas should have a specific gravityapproximately equalling that of air, or a mixture of gases may beapplied, this mixture having substantially the same specific weight asair. Gases of this kind for example are oil gas, acetylene and otherhydrocarbonic gases as C 1 1 C H 0 H and the like. They even have abetter heating quality than gasoline has so that the same eil'ect of themotor atl'ords less fuel. But the main advantage connected with theprovision of such fuel gas instead of liquid fuel is that consumption offuel will cause no, or only a very small, change in equilibrium of theairship as the weight of the gas being consumed is equal to the weightof the air which will occupy its space afterwards. Furthermore it willnot be neces sary to provide lifting gas for the purpose of lifting andcarrying fuel, because my fuel gas will need no support being equal inweight to the surrounding air. Only the necessary space for the fuel gashas to be provided. No lifting gas being wanted for support of the fuelgas the gas space saved in this way may serve for storing the fuel gas.My fuel gas having better heating quality than gasoline the space forits storage may even be smaller than the space saved from the liftinggas space so that the total gas capacity of the airship may also besmaller than that of an airship of the same performance but with liquidfuel. A further advantage resulting from the application of fuel gasaccording to my invention is the circumstance that no special structureor reinforcements need be provided for supporting the fuel so that thedead weight of the airship will be lower than otherwise. This featurewill come into effect especially with rigid airships. Furthermore abetter longitudinal distribution of lifting force and load may beattained thus allowing for better local compensation between these twoforces. This again will allow a certain reduction of structural weight.

Operation of airships according to my invention will also have thefollowing advantage: Gasoline consumption will always have an efiect onthe trim of the ship; with fuel gas of approximately the same specificgravity as air there will not be any influence on the ships trim causedby fuel consumption.

The gas space for lifting gas and that for fuel gas may be completelyseparate from each other. But I prefer to arrange them relative to eachother so that expansion of one of the gases may result in bulgin intothe other gas space if the state of in ation therein does so allow.Besides the two gases may be contained in one common bag or cell or inseparate bags for each gas, or combination gas bags may be providedhaving partition walls dividing them into indivi ual compartments. Withrigid airships where the hull is subdivided by cross members intocompartments the above consideration with regard to the possiblearrangements of gas bags applies to every individual hull compartment.

Another advantage connected with m iiivention ma be pointed out. The cels or bags inten ed for inflation with fuel gas, havin the specificgravity of air, are not reuire to be of the same quality as those inatedwith lifting gas having a very low specific gravity. Therefore, the fuelgas bags may be manufactured from lighter and less expensive material,thereby resulting in a saving both in weight and cost.

Having given a general description of my invention I now want to pointit out more in detail referring to the drawing which represents anexample embodying my invention.

The figure re resents the cross section through a dirigib e airship. Thestrong gas cell 1 is inflated with lifting gas. Cell 3 contains the fuelas and is of light construction only. Ge 2 is adapted to be inflatedwith air for the itrpose of substitutin the consumed fuel gas and toserve as a allonet for securin the shape of the outer cover-7 of theairs ip by means of a blower (not shown) or the like. A piping 6connects cell 3 with engine 5 situated in car 4. The lifting forces ofthe lifting gas are transmitted to the loads by supporting means 8,which may be ropes, wires or other structural elements.

I prefer to press the fuel gas to the motor, but there may as well beprovided a device for sucking it from its container.

It may be advisable to carry also a certain.

amount of liquid fuel in the airship besides the fuel gas. It will thenbe possible to consume such liquid fuel whenever circumstances shouldafford an increase of lift of the airship while travelling. In case afuel gas is CllOf'QIl which is a little lighter than air its consumptionwould cause a decrease of lift of the airship. I prefer to use a fuelgas which is a little heavier than air so that its consumption willcreate a small increase of lift which will be compensated by unavoidablesmall losses of lifting gas and by other unforeseeable circumstancesduring fli ht of the airship.

T do not want to limit myself to the details described or. shown in thedrawin as many variations will occur to those ski ed in the art.

What I claim is:

1. An airship comprising a structure adapted to be inflated with gas; amotor adapted to propel said structure; a gas con-,

tained in said structure and bein of lower specific gravity than air; asecond gas contained in said structure and having a specific gravitysubstantially alike that of air; said first gas being adapted to serveas lifting gas; said second gas being adapted to serve as fuel for saidmotor.

2. An airship comprising a gas cell having lifting gas therein; a secondas cell having fuel as therein of substantially the same specificgravity as air; said first gas cell together with said second cellforming one uniform airship body.

3. An airship comprising a gas cell having lifting gas therein; a secondgas cell having fuel as therein of substantially the same speci cgravity as air; and a structural element. separating said first cellfrom said second cell.

4. An airship comprising a gas cell having lifting gas therein; a secondgas cell having fuel fgas therein of substantiall the same speci cgravity as air; and a exible wall seplarating said first cellfrom saidsecond ce 5. An airship comprising a gas cell having lifting gastherein; a second gas cell having fuel gas therein of substantially thesame specific gravity as air; and an air ballonet operatively associatedwith the gas cells.

6. An airship comprising a gas cell having lifting gas therein; a secondgas cell having fuel gas therein of substantially the same specificgravity as air; a load suspended gravity as air; and load transmittingmeans supported from said first gas cell.

8. An airshi comprising a hull; said hull being 'subdivi ed vertical yinto two com artments; one of said compartments havmg lifting gastherein; the second one of said compartments having gas therein ofsubstantially the same specific gravity as air; and load transmittingmeans supported from said first compartment.

9. An airshi comprisin a hull; said hull being subdivid d verticalfyinto two compartments; one of said compartments havin lifting gastherein; the second one of sai compartments havin gas therein ofsubstantially the same specific gravity as air;an air bag within thehull serving as a ballonet; and load transmitting means supported fromsaid first com artment. I

10. An airs ip comprising a relatively strong structure having liftinggas therein, I

and a relatively light structure having gas therein of substantially thesame specific ravity as air; said two structures together gorming thehull of said airshi EBERHARD LE PERTZ.

